#define _CRT_SECURE_NO_WARNINGS 1
class Solution {
public:
    int longestPalindromeSubseq(string s) {
        int n = s.size();
        vector<vector<int>>dp(n, vector<int>(n));
        for (int i = n - 1; i >= 0; i--)
        {
            dp[i][i] = 1;
            for (int j = i + 1; j < n; j++)
            {
                if (s[i] == s[j])
                    dp[i][j] = dp[i + 1][j - 1] + 2;
                else
                    dp[i][j] = max(dp[i][j - 1], dp[i + 1][j]);
            }
        }
        return dp[0][n - 1];
    }
};